I have integrated the page plugin in my directory.
ruhrlink.de info.php?schluessel=150991 dont work, others do.
When I enter the web adress manually in the developers site -> Page plugin it dont works there, too.
https://www.facebook.com/Geschirr-Service-Ch-Dittrich-607545982758149/
What is so special with this adress?
The page has some sort of access restriction set. The page plugin only works for public pages without any restrictions.
https://developers.facebook.com/docs/plugins/page-plugin#privacy:
Privacy Restricted Pages
Facebook Pages with privacy restrictions cannot be embedded.
来源：https://stackoverflow.com/questions/43140342/facebook-page-plugin-is-not-working-only-for-one-site